package com.sh169.util;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.octo.captcha.service.CaptchaServiceException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

public class VerifyCodeServlet extends HttpServlet{

	/**
	 * 
	 */
	private static final long serialVersionUID = 4392200306396266501L;

	@Override
	protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
			throws ServletException, IOException {
		byte[] captchaChallengeAsJpeg = null;
	       // the output stream to render the captcha image as jpeg into
	        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
	        try {
	        // get the session id that will identify the generated captcha.
	        //the same id must be used to validate the response, the session id is a good candidate!
	        String captchaId = httpServletRequest.getSession().getId();
	        // call the ImageCaptchaService getChallenge method
	            BufferedImage challenge =
	                    CaptchaServiceSingleton.getInstance().getImageChallengeForID(captchaId,
	                            httpServletRequest.getLocale());

	            // a jpeg encoder
	            JPEGImageEncoder jpegEncoder =
	                    JPEGCodec.createJPEGEncoder(jpegOutputStream);
	            jpegEncoder.encode(challenge);
	        } catch (IllegalArgumentException e) {
	            httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
	            return;
	        } catch (CaptchaServiceException e) {
	            httpServletResponse.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
	            return;
	        }

	        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();

	        // flush it in the response
	        httpServletResponse.setHeader("Cache-Control", "no-store");
	        httpServletResponse.setHeader("Pragma", "no-cache");
	        httpServletResponse.setDateHeader("Expires", 0);
	        httpServletResponse.setContentType("image/jpeg");
	        ServletOutputStream responseOutputStream =
	                httpServletResponse.getOutputStream();
	        responseOutputStream.write(captchaChallengeAsJpeg);
	        responseOutputStream.flush();
	        responseOutputStream.close();
	}
	@Override
	protected void doPost(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
			throws ServletException, IOException {
		doGet(httpServletRequest, httpServletResponse);
	}
}
